Remove six of dir cinder/brick,cinder/common,cinder/interface,cinder/objects

Replace the following items with Python 3 style code.

- six.moves
- six.add_metaclass
- six.string_types

Change-Id: Ia46f5967c8e31a17a1614d164e41f8bd81e76f49
Implements: blueprint six-removal

cinder/brick/local_dev/lvm.py

@@ -25,7 +25,6 @@ from os_brick import executor
 from oslo_concurrency import processutils as putils
 from oslo_log import log as logging
 from oslo_utils import excutils
-from six import moves
 
 from cinder import exception
 import cinder.privsep.lvm
@@ -311,7 +310,7 @@ class LVM(executor.Executor):
         lv_list = []
         if out is not None:
             volumes = out.split()
-            iterator = moves.zip(*[iter(volumes)] * 3)  # pylint: disable=E1101
+            iterator = zip(*[iter(volumes)] * 3)  # pylint: disable=E1101
             for vg, name, size in iterator:
                 lv_list.append({"vg": vg, "name": name, "size": size})
 

cinder/common/sqlalchemyutils.py

@@ -20,7 +20,6 @@
 import datetime
 
 from oslo_log import log as logging
-from six.moves import range
 import sqlalchemy
 import sqlalchemy.sql as sa_sql
 from sqlalchemy.sql import type_api

cinder/interface/base.py

@@ -17,8 +17,6 @@
 import abc
 import inspect
 
-import six
-
 if hasattr(inspect, 'getfullargspec'):
     getargspec = inspect.getfullargspec
 else:
@@ -59,8 +57,7 @@ def _get_method_info(cls):
     return result
 
 
-@six.add_metaclass(abc.ABCMeta)
-class CinderInterface(object):
+class CinderInterface(object, metaclass=abc.ABCMeta):
     """Interface base class for Cinder.
 
     Cinder interfaces should inherit from this class to support indirect

cinder/objects/volume_type.py

@@ -14,7 +14,6 @@
 
 from oslo_utils import versionutils
 from oslo_versionedobjects import fields
-import six
 
 from cinder import db
 from cinder import exception
@@ -94,7 +93,7 @@ class VolumeType(base.CinderPersistentObject, base.CinderObject,
             # have to do a conversion here for VolumeTypeProjects ORM instance
             # lists.
             projects = db_type.get('projects', [])
-            if projects and not isinstance(projects[0], six.string_types):
+            if projects and not isinstance(projects[0], str):
                 projects = [p.project_id for p in projects]
             type.projects = projects
         if 'qos_specs' in expected_attrs: